difference between Aromasin and arimidex

Be Prepared to read my freind.


Anastrozole
Arimidex (Anastrozole) is what we call an aromatase inhibitor (AI). In clinical use, it***8217;s used to halt the progression of Breast Cancer in women. It works by blocking the aromatase enzyme, which is responsible for the production of estrogen. In athletics and bodybuilding, it is used as an ancillary compound to be added to a cycle of Anabolic Steroids. In this respect it is also used for its estrogen reducing properties, but it has the additional benefit of increasing testosterone levels, as we***8217;ll see...

Arimidex Side Effects
Many anabolic steroids aromatize (convert to estrogen via the aromatase enzyme), and this is responsible for many of the unwanted side effects found with anabolic steroid use (acne, gynocomastia, water-retention, etc...). In one study, both .5mg and 1mg doses of Arimidex were shown to decrease estrogen by roughly 50%. The 1mg/day dose also increased testosterone levels by 58% (1). In that same study, in both groups, LH and FSH also went up slightly.

Changes in testosterone and E2 concentrations in normal young men (15 22 yr old) before () and after 10 days of oral Anastrozole at 0.5 and 1 mg.(1)

This would seem to suggest that for use during a cycle, a dose of .5mgs/day would be sufficient to combat estrogen-related side effects. It is, however, important to remember that some estrogen is necessary to obtain optimal muscle growth. The lower estrogen levels provided by ´dex seems, anecdotally at least, to produce a more "hard" and "quality" look for bodybuilders who have experimented with it***8217;s use in either a cutting or bulking cycle.

I´d like to point out that the elevation in Testosterone provided by Arimidex is so large that it can be used as a "form" of testosterone replacement therapy for hypogonadal men (2). Clearly, this suggests its use in a post-cycle-therapy (as well as its previously discussed use within a cycle) to regain natural testosterone levels and full functioning of the HPTA (Hypothalamic-Testicular-Pituitary-Axis).

Literature provided by the original maker of Anastrozole (Arimidex, produced by Zeneca Pharmaceuticals) states that stable blood plasma concentrations of the compound are achieved after a mere 7 consecutive 1mg daily doses. Also, Arimidex is just over 80% effective at inhibiting aromatase (3). Thus, if you want to take it for the entire duration of a cycle of anabolic steroids, you can simply start taking it on the same day you begin your cycle. Those are some pretty good numbers, huh?

But can you use it for the entire duration of a cycle? Is it dangerous? Well, certainly reducing estrogen levels in your body is good from a body building point of view, as it reduces water-retention and the potential for gynocomastia (if there***8217;s no estrogen in your body, you can***8217;t get gyno, regardless of how much progesterone is floating around)(5). Luckily this stuff is very mild on blood lipids (cholesterol) and doesn***8217;t affect them adversely (2), in the studies I***8217;ve seen.

Arimidex and Cholestrol
As previously mentioned, those lowered estrogen levels could possibly (eventually) adversely affect your cholesterol and possibly even your immune function. I am, however, very comfortable recommending Arimidex for relatively long-term use. This should be the ancillary compound of choice for those on long and heavy cycles, especially since it also doesn***8217;t inhibit igf like some other ancillary compounds (insulin-like-growth-factor is an important component of anabolism)(4).


Aromasin
Exemestane
Aromasin (Exemestane) is a steroidal suicide aromatase inhibitor, which means that it lowers estrogen production in the body by blocking the aromatase enzyme, the enzyme responsible for estrogen systemization. (1)(2)(3)

This stuff was developed to fight breast cancer in post-menopausal women, who need a particularly aggressive therapy, and for whom first line defenses such as SERMS (Tamoxifen) have not worked. This should be our first clue in inferring that this stuff is pretty strong, or at least stronger than some of the other compounds which are used to fight breast cancer.

Aromasin and Side Effects
Aromasin averages an 85% rate of estrogen suppression (4), so it***8217;s clearly a very effective agent for bodybuilders and other athletes wanting to avoid estrogen related side effects such as gyno, acne, or water-retention brought on by aromatizing steroids. Specifically, Exemestane dose this by selectively inhibiting aromatase activity in a time-dependent and irreversible manner (hence the "suicidal" portion of it***8217;s name, I guess).(7)

As with most of the compounds in this class, it also causes a reasonable rise in testosterone levels (6), and as you may have guessed, this rise in testosterone means that Exemestane can also cause androgenic sides(8)(9)(10). Exemestane is very effective at both lowering estrogen (estradiol) and raising testosterone:
Estrogen and androgen plasma levels after 10 d of daily exemestane (25 or 50 mg) in healthy young males (mean ± SD; n = 9-11). To convert to System International units: estradiol, Pico moles per liter (x3.671); estrone, picomoles per liter (x3.699); androstenedione, nanomoles per liter (*0.003492); and testosterone, nanomoles per liter (x0.03467). (13)

So we can see that 25mgs is a very effective dose from that chart, right? As an added benefit, exemestane not only increases testosterone and lowers estrogen, but it also increases IGF levels (11).Additionally Worth noting is that Aromasin may possibly be less harsh on blood lipids (14)than some of the other (similar) compounds we use in the world of bodybuilding or athletics (other AI´s). It also has, at best no effect on IGF, and at worst could lower (13) it. AI´s are very tricky with regards to inconsistencies in IGF levels.

Unfortunately, you need to take Exemestane for a week to reach steady blood plasma levels of it, and exemestane has a ½ life of 27 hours (12.).

The ability of exemestane to lower estrogen levels by the aforementioned 85% makes it a very nice choice for use in any cycle where aromatizing steroids are used. In addition, since it***8217;s not too harsh at all on blood lipid profiles, it***8217;s a very good choice for longer cycles. It***8217;s ability to raise both testosterone levels also seem to suggest that it would be a very nice addition to a Post-Cycle-Therapy (PCT).
 
I prefer Adex, everyone responds differently so you have to find which works better for you. Both are excellent AI's for on cycle.
 
I'm currently on Week 3 of a 600MG a week Test E cycle taking 0.5MG of Adex EOD. I'm up 7 pounds and don't have any signs of gyno or bloat.
 
I ran adex while on dbol and gyno started to flare up so I switched over to aromasin and it controlled it. I also have read on here that adex has no place in post cycle therapy (pct) where as aromasin does. maybe someone that knows the reason for that will chime in. I do prefer aromasin.
 
BodybuilderX nice write up....

I just wanted attempt to simply it and give a Pharmacist Interns prospective on it.


Arimidex (Anastrozole) is a selective, nonsteroidal aromatase inhibitor so it a competitive aromatase inhibitor. The key to this med is how it achieves the aromatase inhibition. Arimidex is a REVERSIBLE antagonist that binds to the aromatase enzyme. In simple terms arimidex will bind to aromatse preventing the conversion of testosterone to estrogen but after X amount of time it will unbind and testosterone will be able to be converted to estrogen. So while you are taking the med you will have lower estrogen levels but you need to keep taking it. Anastrozole does causes an 85% decrease in estrone sulfate levels. Just because you have lower estrogen levels do not mean that you can not get gynecomastia it will just reduce the chances.

Here are some key points:

-Onset of estradiol reduction: 70% reduction after 24 hours; 80% after 2 weeks therapy
-Duration of estradiol reduction: 6 days
-Absorption: Well absorbed; extent of absorption not affected by food
-Half-life elimination: ~50 hours
-Time to peak, plasma: ~2 hours without food; 5 hours with food



Aromasin (Exemestane) is an IRREVERSIBLE steroidal aromatase inactivator. That is it irreversibly blocks the active site of the aromatase enzyme for the life of the enzyme, leading to inactivation (***8220;suicide inhibition***8221;) and thus preventing conversion of androgens to estrogens in peripheral tissues. Remember that your body will produce more aromatase enzymes.

Some more key points
-Absorption: Rapid and moderate (~42%) following oral administration; absorption increases ~40% following high-fat meal
-Half-life elimination: 24 hours
-Time to peak: Women with breast cancer: 1.2 hours



Both meds have good benefits but I would lean towards Arimidex for estrogen control because you dont want your estrogen to low and I am sure many people on here are not getting there estrogen levels checked. I have to stress that neither one of these meds will prevent gynecomastia. They will how ever help reduce the chances of it developing. If you are on either one of these or are sensitive to estrogen and start to devlop signs of gynecomastia then you might want to get some Nolvadex. Nolvadex is the only one that has properties which compete with estrogen for binding sites in breast.
 
I ran adex while on dbol and gyno started to flare up so I switched over to aromasin and it controlled it. I also have read on here that adex has no place in pct where as aromasin does. maybe someone that knows the reason for that will chime in. I do prefer aromasin.

Because during PCT, Tamoxifen greatly reduces the effectiveness of Arimidex. There is no drug interaction between Aromasin and Tamoxifen though so, it is preferred for PCT use.
Arimidex and Tamoxifen Hexal Drug Interactions - Drugs.com
 
For those of you running aromasin, could you please tell me what your daily intake is and provide body weight.

At 56 yeras old, 192 lbs 16 % bf, on 500 mg test e per week, I have been running 12.5 mg ed based on my morning bp reading alone. Any lower a dose and my bp starts to go up too much. But I do not know id this is optimal from an estrogen point of view.

In my 6th week of the cycle, my strength has really improved significantly in the gym, but I feel rather lazy all the time (which is not normal for me). Feel like napping a lot. Also my weight has not gone up very much yet (5 lbs) and my libido is not as some report extreme.

Does all this sound ok ? Or should i try to bump up the aromasin to be less lethargic ?

My test is from AML and is widely reported on this forum as g2g and potent
 
For those of you running aromasin, could you please tell me what your daily intake is and provide body weight.

At 56 yeras old, 192 lbs 16 % bf, on 500 mg test e per week, I have been running 12.5 mg ed based on my morning bp reading alone. Any lower a dose and my bp starts to go up too much. But I do not know id this is optimal from an estrogen point of view.

In my 6th week of the cycle, my strength has really improved significantly in the gym, but I feel rather lazy all the time (which is not normal for me). Feel like napping a lot. Also my weight has not gone up very much yet (5 lbs) and my libido is not as some report extreme.

Does all this sound ok ? Or should i try to bump up the aromasin to be less lethargic ?

My test is from AML and is widely reported on this forum as g2g and potent

There is not a soul on here that can give you 100% accurate information regarding that. What you need is a blood panel (especially since your 6wks in) to see concrete estradiol levels among other things. I just had mid cycle bloods done and while I "thought" I had crashed my E, the actual number was well above reference range. Symptoms are a good way to adjust dosing in the beginning but they will not beat the accuracy of a real blood panel coupled with experience.


Edit* Aromatase inhibitor (AI) dosing also has very little to do with body weight. If you're highly estrogen sensitive, highly prone to aromatization, etc it will affect your Aromatase inhibitor (AI) needs but those aren't dependent on "stats" per se.
 
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For those of you running aromasin, could you please tell me what your daily intake is and provide body weight.

At 56 yeras old, 192 lbs 16 % bf, on 500 mg test e per week, I have been running 12.5 mg ed based on my morning bp reading alone. Any lower a dose and my bp starts to go up too much. But I do not know id this is optimal from an estrogen point of view.

In my 6th week of the cycle, my strength has really improved significantly in the gym, but I feel rather lazy all the time (which is not normal for me). Feel like napping a lot. Also my weight has not gone up very much yet (5 lbs) and my libido is not as some report extreme.

Does all this sound ok ? Or should i try to bump up the aromasin to be less lethargic ?

My test is from AML and is widely reported on this forum as g2g and potent

I would recommend getting some bloodwork, you can do it through privatemdlabd/labcorp and get results within 24-48 hrs. Select female hormone panel and check out as a male to get proper ranges. It would be that your estrogen is too high or low. I read somewhere on another forum that a good dose for Aromasin while on cycle is 25mg ED not 12.5mg ED due to its short half life in males. But as with everything, everyone reacts differently... so take it with a grain of salt.
 
There is not a soul on here that can give you 100% accurate information regarding that. What you need is a blood panel (especially since your 6wks in) to see concrete estradiol levels among other things. I just had mid cycle bloods done and while I "thought" I had crashed my E, the actual number was well above reference range. Symptoms are a good way to adjust dosing in the beginning but they will not beat the accuracy of a real blood panel coupled with experience.


Edit* Aromatase inhibitor (AI) dosing also has very little to do with body weight. If you're highly estrogen sensitive, highly prone to aromatization, etc it will affect your Aromatase inhibitor (AI) needs but those aren't dependent on "stats" per se.

^ This
Sorry I didn't read until after I posted above.
 
sounds to me aromasin is the better of the two... would you think its better then adex for gyno sensative people? or just kind of have to find out for yourself?
 
Do aromaisin give you nausea and headaches? I use rui liquid adex and it makes me feel very ill. I may consider aromaisin.
 
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